Safety valves



Nov. 19; 1957 v. w. FARRIS 2,813,539

SAFETY VALVES Filed Nov. 1, 1955 2 Sheets-Sheet 1 INVENTOR ,y VICTOR w FARR/S Arron/vs? V. W. FARRIS SAFETY VALVES mvswd T R- W FAR/21S 1. g 2 v r B W Nov. 19, 1957 Filed Nov. 1, 1955 ATTORNEY SAFETY VALVES Victor W. Farris, Palisades Park, N. J.

Application November 1, 1955, Serial No. 544,249

9 Claims. (Cl. 137-469) This invention relates to safety valves, and more particularly to safety valves wherein both short warn and short blow-down are attained by a single adjustment.

In a co-pending application, Serial No. 541,364, filed October 19, 1955, there is described a safety valve in which warn and blow-down are controlled by independent adjustments. As shown in said co-pending application, a first adjustment controls the position of a sliding ring with respect to a valve disk prior to discharge to govern the speed of the warn, and a second adjustment limits the amount of the sliding movement of said ring during discharge to govern the speed of the blow-down. It has been found that with such an arrangement, static pressure of the fluid to be discharged causes some premature movement of the ring, and this upsets the desired close control over the speed of the warn. It is to the elimination of this disadvantage that the present invention is addressed.

In the invention to be described herein, there are, in effect, separate warn and blow-down rings the positions of which, with respect to the valve disk, are controlled by a single adjustment. The blow-down ring is rotatably mounted on the warn ring and the construction and movement of the blow-down ring are such that static pressure of the fluid during the early stages of discharge, i. e., prior to attainment of maximum velocity of the discharge, has practically no effect upon the movement of said blow-down ring. However, as soon as the valve has opened to its maximum capacity, and this occurs with a very short warn, the velocity of the discharging fluid acts upon the blow-down ring to move it to its maximum position and retain it there throughout discharge thereby to permit speedy blow-down at the termination of the discharge. 1 Inthe accompanying drawings,

Fig. 1 is a vertical sectional view of a safety valve made in accordance with the present invention;

Fig. 2 is an enlarged, fragmentary View of the same;

Fig. 3 is a transverse sectional View taken along line 3-3 of Fig. 2;

Fig. 4 is a like View taken along line 44 of Fig. 2; and

Fig. 5 is a view similar to Fig. 4 but with the parts in their positions at a different stage in the operation of the valve.

Referring now more in detail to Figs. 1 to 4, inclusive of the drawings, the reference character generally designates a safety valve including a valve body 11 having a central chamber 12, inlet port 13 and outlet port 14. Mounted on the body 11 is a bonnet 15 providing a spring chamber 16 and at the upper end of the bonnet is a cap 17. Threadedly engaged in the inlet port 13 is a nozzle 13 at the inner end of which a valve seat 19 is formed.

Cooperable with the seat 19 is a valve disk 29, said disk being disposed in a recess 21 formed in the underside of a disk-holding member 22. Rising from the upper surface of the disk 29, at the center thereof, is a rod having an enlarged threaded head 23 adapted to be received in a socket 24 formed in the holding member 22.

fa Patnt ice The socket 24 of the holding member 22 is, in turn, threadedly engaged in the lower end of a cylindrical disk guide 25 slidably mounted in a sleeve 26 carried in a baflie 27. The battle is secured, at the periphery thereof, between the valve body 11 and the bonnet 15 and serves to isolate the central chamber 12 of the body 11 from the spring chamber 16 of the bonnet 15. This isolation is aided by a bellows 28 one end of which is anchored between the baffle 27 and the valve body 11 and the other end of which is anchored between the guide 25 and the holding member 22.

The upper end of the guide 25 is provided with a socket 29 receptive of an enlarged threaded head 30 formed on the lower end of a valve stem 31. The upper end of the stem is slidably mounted in a spring pressure adjusting screw 32 adapted to be locked in place after adjustment by a lock nut 33. The lower end of the screw 32 engages a button 34 which bears against the upper end of a spring 35, the lower end of the latter contacting another button 36 which is urged against an enlargement 37 formed on the stem 31. Threaded on the upper end of the screw 32 is a lock nut 38 adapted to engage a manual control (not shown) for test lifting the valve disk 20..

Surrounding the disk 20 and formed on the holding member 22 is a depending flange 39, said flange having an interior surface 40 which flares outwardly from a flat, secondary disk area 41 presented by the undersurface of the holding member 22, in a direction opposite to the flow of fluid through the nozzle 18.

Threadedly engaged on the nozzle 18, a short distance below the seat 19, is a ring 42 provided about its periphcry with serrations 43 engageable by a locking screw 44 carried in the valve body 11. Rising from the upper edge of the ring 42, in spaced relation to the nozzle 18 to provide an annular channel 45 therebetween, i a collar 46 having a plurality of openings 47 therein. The upper end 48 of the collar 46 is bevelled and is adapted, by adjustment of the ring 42, to cooperate with the secondary disk area 41 of the holding member 22 to present a gap therebetween governing the speed of the warm as hereinafter more fully explained.

Surrounding the collar 46 and bearing on a shoulder formed on the ring 42 is a second ring 49 provided, like the collar 46 (see Fig. 4), with a plurality of openings 50 therein, rotation of this second ring governing the blow-down of the valve as will be hereinafter more fully described. Intermediate the openings 50, the ring 49 is provided, on its outer surface, with a plurality of angularly disposed vanes 51. The ring 49 is also recessed to receive a torsion spring 52 one end 53 of which is anchored in the collar 46 and the other end 54 of which is anchored in the ring 49 itself. The force exerted by this spring is sufficient only to maintain the rings 49 and 42 in such relative rotational position that, in the absence of discharge through the valve, the openings 50 and 47 are laterally displaced with respect to each other. This completes the description of the safety valve of the present invention and the operation thereof may be summarized as follows:

At the outset, the ring 42 is rotated until the end 42; of the collar 46 just contacts the secondary disk area 41 of the holding member 22. Then, by rotating the ring 42 in the opposite direction, the collar is backed away from the holding member until a small gap is provided between the end 48 of the collar and the area 41 of the holding member, the magnitude of the gap depending upon the desired shortness of the Warn. The smaller the gap, the shorter the warn. After making this adjustment, the ring 46 is locked against rotation by the screw 44. At this time, by virtue of the expanding tendency of the spring 52, the blow-down ring 49 will be so rotationally disposed with respect to the collar 46 3 that the openings 47 and 50 in the ring 49 and collar 46, respectively, will be relatively displaced, as shown in Fig. 4-.

As the pressure of the fluid to be discharged; reaches a value suflicient to overcome the closing force of the spring 35, the valve disk Ztlbegins t lifLpermitting the fluid to enter the region roughly defined by the holding member 22 and the collar 46. Because, of the small gap between the end 48. of the collar 46 and thesecondar y disk area 41, the fluid is restricted and quickly. builds, up appreciable pressure against the secondary disk area 41. As a result of the augmented area against which the fluid can act, the total pressure exerted by it causes the valve quickly to open to its maximum capacity,

other words, to discharge with a short warn.

As the discharging fluid passes between the collar 46 and the secondary disk area 41, it acts upon the vanes. 51 of the ring. 49, the velocity of the discharging fluid causing rotation of the ring 49, against the light restraining action of the spring 52, until the openings 5% in the ring 49 become alined with the openings 4''? in the collar 46, as shown in Fig. 5. As a result, fluid from the channel 45 can also discharge toward the valve outlet port 14.

Because the spring 52 is of such a nature that it can only exert a very light force, the ring 49 remains in such position as to aline the openings 47 and 5 b throughout the discharge. As a result, the substantially unrestricted passage between the inlet and outlet ports of the valve prevents building up any back pressure to oppose the closing force of the spring 35 and the valve disk 29 returns to its seat 19 substantially at the end of the discharge. In other words, there is a short blow-down. Once the valve has closed, the force of the spring 525; is sufficient to rotate the ring 49 back to its initial posi: tion with the openings 5d and 47 displaced with respect to each other.

This completes the description of the mode of operation of the present invention.

What is claimed is:

1. A safety valve comprising: a valve body having inlet and outlet ports; a valve disk cooperating with a valve seat to control discharge between said inlet and outlet ports; a first ring, adjustable with respect to said valve disk, to control the predischarge relationship therebetween; and a second ring carried by said first ring and provided with vanes angularly disposed with respect to the path of the discharge through said valve whereby said discharge causes relative rotational movement between said rings; said rings being provided with open: ings which are displaced with respect to each other prior to discharge of said valve, and which become alined by the relative movement between said rings resulting from the discharge of said valve.

2. A safety valve comprising: a valve body having inlet and outlet ports; a valve disk cooperating with a valve seat to control discharge between said inlet and outlet ports; a first ring, surrounding said inlet port, in spaced relation thereto to thereby provide an annular channel therebetween; a portion of said first ring being threadedly engaged with said inlet port for adjustment toward and away from said valve disk to control the predischarge relationship between said first ring and said valve disk; and a second ring carried by said first ring and provided with vanes angularly disposed with respect to the path of the discharge through said valve whereby said discharge causes relative rotational movement between said rings, said rings being provided with openings which are displaced with respect to each other prior to discharge of said valve, and which become alined by the relative movement between said rings resulting from the discharge of said valve.

3. A safety valve comprising: a valve body having inlet and outlet ports; a valve disk cooperating. with a valve se t t csntw sch r w n said l t d outlet ports; a first ring, adjustable with respect to said valve disk, to control the predischarge relationship therebetween; a second ring carried by said first ring and pro vided with vanes angularly disposed with respect to the path of the discharge through said valve whereby said discharge causes relative rotational movement between said rings, said rings being provided with openings which are displaced with respect to each other prior to discharge of said valve, and which become alined by the relative movement between said rings resulting from the discharge of said valve; and a torsional spring having its ends secured, respectively, to said first and second rings to restore said rings to their initial relative position after completion of the discharge through said. valve.

4. A safety valve comprising: a valve body having inlet and outlet ports; a valve disk cooperating with a valve seat to control discharge between said inlet and outlet ports; a first ring, surrounding said inlet port, in spaced relation thereto to thereby provide an annular channel therebetween; a portion of said first ring being threadedly engaged with said inlet port for adjustment toward and away from said valve disk to control the predischarge relationship between said first ring and said valve disk; a second ring carried by said first ring and provided with vanes angularly disposed with respect to the path of the discharge through said valve whereby said discharge causes relative rotational movement between said rings, said rings being provided with openings which are displaced with respect to each other prior to discharge of said valve, and which become alined by the relative movement between said rings resulting from the discharge of said valve; and a torsional spring having its ends secured, respectively, to said first and second rings to restore said rings to their. initial relative posi tion after completion of the discharge through said valve.

5. A safety valve comprising: a valve body having inlet and outlet ports; a valve disk cooperating with a valve seat to control discharge between said inlet and outlet ports; first and second rings mounted for relative rotation in said valve body; said first ring being adjustable with respect to said valve disk to control the predischarge relationship therebetween; said second ring being provided with means reacting to the discharge through said valve to cause relative rotation between said first and second rings; both of said rings being provided with openings which are displaced with respect to each other prior to discharge of said valve, and which become alined by the relative movement between said rings resulting from the discharge of said valve.

6. A safety valve comprising: a valve body having inlet and outlet ports; a valve disk cooperating with a valve seat to control discharge between said inlet and outlet ports; first and second rings mounted for relative rotation in said valve body; said first ring surrounding said inlet port, in spaced relation thereto, to thereby provide an annular channel therebetween, a portion of said first ring being threadedly engaged on said inlet port for adjustment toward and away from said valve disk to control the predischarge relationship therebetween; said second ring being provided with means reacting to the discharge through said valve to cause relative rotation between said first and second rings; both of said rings being provided with openings which are displaced with respect to each other prior to discharge of said valve, and which become alined by the relative movement between said rings resulting from the discharge of said valve.

7. A safety valve comprising: a valve body having inlet and outlet ports; a valve disk cooperating with a valve seat to control discharge between said inlet and outlet ports; first and second rings mounted for relative rotation in said valve body; said first ring being adjustable with respect to said valve disk to control the predischarge relationship therebetween; said second ring being provided with means reacting to the discharge through said valve to cause relative rotation between said first and second, rings;

both of said rings being provided with openings which are displaced with respect to each other prior to discharge of said valve, and which become alined by the relative movement between said rings resulting from the discharge of said valve; and means associated with said rings for restoring the initial relationship therebetween at the completion of the discharge through said valve.

8. A safety valve comprising: a valve body having inlet and outlet ports; a valve disk cooperating with a valve seat to control discharge between said inlet and outlet ports; first and second rings mounted for relative rotation in said valve body; said first ring being adjustable with respect to said valve disk to control the predischarge relationship therebetween; said second ring being provided with means reacting to the discharge through said valve to cause relative rotation between said first and second rings; both of said rings being provided with openings which are displaced with respect to each other prior to discharge of said valve, and which become alined by the relative movement between said rings resulting from the discharge of said valve; and a torsional spring having its ends secured, respectively, to said first and second rings to restore said rings to their initial relative position after completion of the discharge through said valve.

9. A safety valve comprising: a valve body having inlet and outlet ports; a valve disk cooperating with a valve seat to control discharge between said inlet and outlet ports; first and second rings mounted for relative rotation in said valve body; said first ring surrounding said inlet port, in spaced relation thereto, to thereby provide an annular channel therebetween, a portion of said first ring being threadedly engaged on said inlet port for adjustment toward and away from said valve disk to control the predischarge relationship therebetween; said second ring being provided with means reacting to the discharge through said valve to cause relative rotation between said first and second rings; both of said rings being provided with openings which are displaced with respect to each other prior to discharge of said valve, and which become alined by the relative movement between said rings resulting from the discharge of said valve; and a torsional spring having its ends secured, respectively, to said first and second rings to restore said rings to their initial relative position after completion of the discharge through said valve.

References Cited in the file of this patent UNITED STATES PATENTS 

